Abrasive composition



Patented Feb. 6, 192a.

FEE.

HANS M. OLSON, F BURBANK, CALIFORNIA.

ABRASIVE COMPOSITION.

No Drawing.

To all whom it 114 ay cowcern- Be it known that I, HANS M. OLSON, a citizen of the United States, residing at. Burbank, in the county of Los Angeles and State of California, have invented new and useful Improvements in Abrasive Composiz ons, of which the following is a specifica- This invention relates to an abrasive composition and to the method of making same.

It is the object of this invention to provide an abrasive substance and a means for forming same from diatomaceous earth by adding thereto such ingredients as when subjected to high temperature as to convert the natural soft non-crystalline formation thereof into an extremely hard crystalline formation.

Diatomaceous earth when pulverized forms a soft chalky powder free from grit and is not suitablefor abrasive or polishing purposes as the minute particles thereof are round or smooth and are capable of little or no abrasive action, but by adding certain ingredients and treating same as hereinafter set forth the particles are changed to sharp crystalline form of such minuteness as to retain in appearance and to the touch the physical characteristic of soft and chalky powder. 1

The term diatomaceous earth is interchangeable and coextensive with'the terms kieselguhr, non-crystalline silica, and infusorial earth, and is to be here construed as inclusive of these terms as well as all other synonymous terms, and is ,also meant to include all earth having qualities and characteristics similar to diatomaceous tion as set forth in the appended claims.

For example it is possible to obtain like results by using a mixture of a suitable metal- Application filed October 21, 1918. Serial No. 258,951v

lic sulfate and any suitable alkaline sulfate in lieu of alum, such as a mixture comprising one-half aluminum sulfate and one 56 half sodium sulfate. Any other suitable metallic sulfate may be used in place of aluminum sulfate, and any other suitable alkaline sulfate may be used in lieu of sodium sulfate.

The proportions of the diatomaceous earth and the binder may be varied considerably according to the particular quality of product desired without departing from the invention as set forth in the claims, but a preferable mixture or composition is produced by using;

88% dry pulverized diatomaceous earth, 2% alum, and 10% lime.

Ordinarily the limits to which the difierent ingredients may be used are seventy-five to ninety-five per cent diatomaceous earth to the entire mass and a binder and crystallizing agent of from five to twenty five per cent of the entire mass.

The steps for forming my new abrasive composition are as follows: I

First. The ingredients are finely pulverized and thoroughly commingled in a dry state.

Second. Water is added to efiect a close mixture and to start a chemical action by which the diatomaceous earth is changed from a non-crystalline silica to a crystalline silica, the Water being added in such quantity as to form a dry paste. From 75% to 200% of water by volume in proportion to the mass is generally employed.

Third. The moisture is evaporated from the mixture, either shortly after the addition of water orthe mass may be allowed to stand, say 24 hours, to prolong the chemical action. This evaporation may be efl'ected either by natural or artificial means.

Fourth. The mass in a lumpy state is sub- W jected to the action of heat gradually increased from approximately 800 F. to 2700 F which acts to accelerate and complete the crystallization and render the crystals hard. The degree of hardness imparted I to the crystals is governed by the extreme of heat to which the substance is subjected, and it may be heated to a temperature of 3000 F. or more without fusing or during.

The product resulting from the foregoing alum, and lime, which have collectively been may be ground to any desired degree of subject to the action of Water and calcined. 10

- fineness Without destroying its hard or stal- 2. The herein described composition of line character though retaining the so t apmatter consisting of seventy-five to ninety 5 pearance of the natural diatomaceous earth. five parts of non-crystalline silica, and 5 1 claim; to 25 parts lime and alum, which have been 1. The herein described composition of mixed with water and calcined. matter consisting of non-crystalline silica, HANS. M. OLSON. 

